Systems and methods for treatment of sleep apnea

ABSTRACT

A method of treating an airway disorder includes placing an implant in a patient&#39;s tongue, wherein the implant has first and second end portions that attach to tissue, and a tensioned medial portion between the first and second ends. The medial portion is configured to apply a pressure of less than a predetermined amount. Device systems associated with such methods are also provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to: U.S. Provisional Application No.61/367,707 filed Jul. 26, 2010; U.S. Provisional Application No.61/418,238 filed Nov. 30, 2010; U.S. Provisional Application No.61/419,690 filed Dec. 3, 2010.

INCORPORATION BY REFERENCE

This application is related to co-pending patent applications: U.S.application Ser. No. 11/969,201 filed Jan. 3, 2008; U.S. applicationSer. No. 12/937,564 filed Jan. 3, 2011; U.S. application Ser. No.13/053,025 filed Mar. 21, 2011; U.S. application Ser. No. 13/053,059filed Mar. 21, 2011; U.S. application Ser. No. 13/113,933 filed May 23,2011; and U.S. application Ser. No. 13/113,946 filed May 23, 2011. Allpublications, patents and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent or patent application wasspecifically and individually indicated to be incorporated by reference.

FIELD

The disclosure relates to the field of methods and devices for thetreatment of obstructive sleep apnea, and more particularly to openingthe airway of subjects with symptoms of obstructive sleep apnea.

BACKGROUND

Sleep apnea is defined as the cessation of breathing for ten seconds orlonger during sleep. During normal sleep, the throat muscles relax andthe airway narrows. During the sleep of a subject with obstructive sleepapnea (OSA), the upper airway narrows significantly more than normal,and during an apneic event, undergoes a complete collapse that stopsairflow. In response to a lack of airflow, the subject is awakened atleast to a degree sufficient to reinitiate breathing. Apneic events andthe associated arousals can occur up to hundreds of times per night, andbecome highly disruptive of sleep. Obstructive sleep apnea is commonlybut not exclusively associated with a heavy body type, a consequence ofwhich is a narrowed oropharyngeal airway.

Cyclic oxygen desaturation and fragmented sleeping patterns lead todaytime sleepiness, the hallmark symptom of the disorder. Furtherconsequences of sleep apnea may include chronic headaches anddepression, as well as diminished facilities such as vigilance,concentration, memory, executive function, and physical dexterity.Ultimately, sleep apnea is highly correlated with increased mortalityand life threatening co-morbidities. Cardiology complications includehypertension, congestive heart failure, coronary artery disease, cardiacarrhythmias, and atrial fibrillation. OSA is a highly prevalent diseasecondition in the United States. An estimated 18 million Americans sufferfrom OSA to degrees that range from mild to severe, many of whom areundiagnosed, at least in part because the afflicted subjects are oftenunaware of their own condition.

Treatment of OSA usually begins with suggested lifestyle changes,including weight loss and attention to sleeping habits (such as sleepposition and pillow position), or the use of oral appliances that can beworn at night, and help position the tongue away from the back of theairway. More aggressive physical interventions include the use ofbreathing assist systems that provide a positive pressure to the airwaythrough a mask that the subject wears, and which is connected to abreathing machine. In some cases, pharmaceutical interventions can behelpful, but they generally are directed toward countering daytimesleepiness, and do not address the root cause. Some surgicalinterventions are available, such as nasal surgeries, tonsillectomyand/or adenoidectomy, reductions in the soft palate, uvula or the tonguebase, or advancing the tongue base by an attachment to the mandible andpulling the base forward. These surgical approaches can be quiteinvasive and thus have a last-resort aspect to them, and further, simplydo not reliably alleviate or cure the condition. There is a need forless invasive procedures that show promise for greater therapeuticreliability. There is additional need for the ability to reverseprocedures or otherwise revise the procedure, thus allowing for theability to reverse or otherwise revise the effects of the procedure dueto side effects or other undesirable outcomes which may result from theprocedure. Additionally, there is the need to do these proceduralreversals or revisions in a manner that does not require excessivetissue cutting or invasiveness which can act as a deterrent for patientsor physicians to perform such a revision procedure.

SUMMARY

The invention relates to a method of alleviating obstructive collapse ofairway-forming tissues, and for devices with which to implement themethod. Typical patients for whom the method and device may providetherapeutic benefit are those who suffer from obstructive sleep apnea.The method includes implanting a device at a site in the tissue andbioeroding the bioerodible portion of the device to change the shape ofthe device and to remodel the airway-forming tissue. The implanteddevice is sized and shaped to conform to the airway-forming tissue sitein a manner compatible with normal physiological function of the site;and includes a resiliently deformable portion and a bioerodible portion.In typical embodiments of the method, remodeling the airway-formingtissue results in the airway being unobstructed during sleep, andfurther, typically, the thus-unobstructed airway diminishes thefrequency of apneic events. Remodeling may include reshaping orotherwise altering the position or conformation of airway associatedtissue so that its tendency to collapse during sleep is diminished.

The airway is formed from various tissues along its length from themouth to the lungs. Embodiments of the method include implanting aresilient implant, such as an elastomeric device, into any one or moreof these tissues, including, for example, the soft palate, the tongue,generally the base of the tongue, and the pharyngeal walls, typicallythe posterior and lateral portions of the pharyngeal wall.

In some embodiments, the device is in a deformed shape when implanted,and a bioerodable portion erodes to thereby release a tensioned shape ofthe implant to apply retraction forces to the site.

With regard to the bioeroding of the bioerodible portion of the device,this may occur over a time span that ranges from days to months. In someembodiments, the bioeroding proceeds at a rate that correlates with theratio of the biologically-exposed surface area of the bioerodibleportion to the volume of the bioerodible portion.

In some embodiments of the method, the bioerosion occurs at a rate thatis sufficiently slow for the tissue site to recover from the implantingprior to the device substantially changing shape. In some of theseembodiments, the recovery of the tissue site includes a forming offibrotic tissue around the device, which typically stabilizes the devicein the site, and provides the device greater leverage with which toreform the shape of the implant site and its surrounding tissue. In someembodiments, after implanting, and as part of the healing response orrecovery from the implantation wound, the newly formed fibrotic tissuesinfiltrates into holes, pores, or interstices in the device. In someembodiments of the method, a bioactive agent, previously incorporatedinto the bioerodible material, is released or eluted from thebioerodible portion of the device as it is eroding.

In another aspect of the methods described herein, a method of forming adevice to alleviate obstructive collapse of an airway during sleep isprovided. The method includes forming a resiliently deformable materialinto an, initial shape that corresponds to the preferred shape of thedevice, the initial shape having a site for accommodating bioerodiblematerial; changing the initial shape of the resiliently deformablematerial into a non-preferred shape that is sized and configured into animplantable shape that conforms to an airway-forming tissue site and iscompatible with normal physiological function after implantation; andstabilizing the implantable shape by incorporating the bioerodiblematerial into the accommodating site. In some of these methodembodiments, changing the initial shape of the resiliently deformablematerial includes absorbing a force sufficient to remodel the airway asthe force is transferred from the device into an implant site afterimplantation of the device. That level of force is further typicallyinsufficient to remodel the airway to an extent that it is unable tomove in a manner that allows substantially normal or acceptablephysiological function of the airway.

As noted above, some aspects of the disclosure further provide a devicefor alleviating obstruction in an airway, such obstruction typicallyoccurring during sleep. Embodiments of the device include an implantabledevice sized and shaped to conform to an airway-forming tissue site in amanner compatible with normal physiological function of the site, thedevice including a resiliently deformable portion and a bioerodibleportion. In these embodiments, the resiliently deformable portion has apreferred shape that is constrained in a deformed shape by thebioerodible portion, and the device is configured to return toward thepreferred shape of the resiliently deformable portion upon erosion ofthe bioerodible portion. In some embodiments, the preferredconfiguration is adapted to remodel the shape of the airway so as toprovide a more open airway during sleep.

In typical embodiments of the device, the resiliently deformable portionmay include any one or more of a metal or a polymer. In theseembodiments, a resiliently deformable metal may include any one or moreof stainless steel, spring steel, or superelastic nickel-titanium alloy,and a resiliently deformable polymer may include any one or more ofsilicon rubber, polyesters, polyurethanes, or polyolefins. In someembodiments, the bioerodible portion may include any one or more ofpolycaprolactone, polylactic acid, polyglycolic acid, polylactidecoglycolide, polyglactin, poly-L-lactide, polyhydroxalkanoates, starch,cellulose, chitosan, or structural protein.

Some embodiments of the device include a portion adapted to engage thetissue into which it is implanted, and in some of these embodiments, theso-adapted portion includes a site for tissue in-growth, such in-growthserving to keep the device and tissue in close proximity, serving topromote implant site remodeling in a manner that conforms to thechanging shape of the device. Finally, in some embodiments, theimplantable device is configured with sufficient elasticity to allownormal physiological movement around an airway-forming tissue implantsite when the device is implanted in the implant site.

In other embodiments, the adapted portion contains sites for tissue tolink through the implant after implantation forming tissue plugs whichthus form an attachment between the implant and the adjacent tissuewithout a corresponding adhesion of tissue to the implant. This type ofarrangement can produce an implant that can effectively attach to andmove tissue while remaining easily removable from the tissue. The tissueplugs can be formed by linking the implant around an encircled mass oftissue or allowing tissue to heal through the implant thus forming theisland of encircled tissue. Implants can contain one or more encircledmasses of tissue allowing attachment to the adjacent tissue.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 provides an overview of the healthy human airway anatomy, withparticular attention to the nasopharyngeal, oropharangeal, andhypopharyngeal regions.

FIG. 2A provides a view of a compromised airway, with an occlusion inthe oropharyngeal region due to posterior slippage of the base of thetongue.

FIG. 2B provides a view of a compromised airway with palate closure.

FIG. 3A depicts an elongate implant component of a revisable OSA implantsystem, the implant having end portions with openings for growth of atissue plug therethrough to secure the end portions in a treatment site.

FIG. 3B is a cut-away view of an end portion of the implant of FIG. 3Ain a tissue site.

FIG. 3C depicts another elongate implant embodiment similar to that ofFIG. 3A.

FIG. 3D depicts another elongate implant embodiment.

FIG. 4 depicts another elongate implant corresponding to aspects of theinvention.

FIG. 5A depicts a second component of a revisable OSA implant system,the second component comprising a cutting tool.

FIG. 5B depicts the cutting tool of FIG. 5A in a method of use.

FIG. 6 depicts an alternative cutting tool similar to that of FIGS.5A-5B.

FIG. 7A depicts another elongate implant corresponding to aspects of theinvention.

FIG. 7B depicts another elongate implant embodiment.

FIG. 7C depicts another elongate implant embodiment.

FIG. 7D depicts another elongate implant embodiment with multipleopenings in multiple planes.

FIG. 7E is a partially cut-away view that depicts an OSA implant with anelastomeric portion that is configured for being releaseably maintainedin a tensioned or non-repose condition by a magnesium or magnesium alloybiodissolvable material or element.

FIG. 8A depicts the working end of another embodiment of a cutting toolfor cutting a portion of an implant in situ.

FIG. 8B depicts another embodiment of a cutting tool for cutting animplant in a revision procedure.

FIG. 9 depicts another implant with a medial portion having a surfaceconfigured for low adhesive energy.

FIG. 10 depicts another elongate implant corresponding to aspects of theinvention.

FIG. 11 depicts another implant corresponding to aspects of theinvention including a sacrificial portion that can be sacrificed inresponse to an external stimulus.

FIG. 12 is a cut-away view depicting the implant of FIG. 11 in a tissuesite after actuation of the sacrificial portion of the implant.

FIG. 13A depicts an alternative implant including an electrolyticallysacrificial portion that can be sacrificed in response to a directcurrent.

FIG. 13B is a cut-away view depicting the implant of FIG. 13A in atissue site after actuation of electrolytic connection portion of theimplant.

FIG. 14 depicts an end portion of an alternative revisable implantincluding a cut wire for cutting a tissue plug.

FIG. 15 is a cut-away view depicting the implant of FIG. 14 in a tissuesite in the process of actuating the cut wire.

FIG. 16 depicts an end portion of an alternative revisable implantincluding a cut wire for cutting a plurality of tissue plugs.

FIG. 17 depicts an alternative revisable OSA implant.

FIGS. 18A and 18B illustrate an end portion of the revisable implant ofFIG. 17.

FIG. 19 depicts an alternative revisable OSA implant.

FIG. 20 depicts a revisable OSA implant that allows for in-situpost-implant adjustment of the retraction forces applied to tissue bythe implant.

FIG. 21 depicts an alternative revisable OSA implant that allows forin-situ post-implant adjustment of the retraction forces.

FIGS. 22 and 23 depict another revisable OSA implant that allows forin-situ post-implant adjustment of the retraction forces.

FIG. 24 depicts an OSA implant with first and second anchoring endsimplanted in a particular site in a patient's tongue.

FIG. 25 depicts the OSA implant of FIG. 24 implanted in anotherparticular site in a patient's tongue.

FIGS. 26-27 depict a plurality of OSA implants each with first andsecond anchoring ends implanted in a patient's tongue for applyinglinear-directed forces in different distinct vectors.

FIGS. 28A, 28B and 28C depict another OSA implant system for applyinglinear-directed forces in different distinct vectors with individualimplant bodies coupled together in-situ with attachment means.

FIGS. 29A-29B depict another OSA implant system similar to that of FIGS.28A-28C for applying linear-directed forces in different distinctvectors in a different orientation.

FIG. 30 illustrates a method of utilizing a cannula apparatus fordeployment of an OSA implant as in FIG. 24 in a particular site in apatient's tongue.

FIG. 31 illustrates a working end of the cannula apparatus of FIG. 30together with a push rod or stylette mechanism for deployment of the OSAimplant of FIG. 24.

FIGS. 32A-32B illustrate a method of utilizing an alternativetelescoping cannula apparatus for deployment of an OSA implant at aselected angle in a patient's tongue.

FIG. 33 illustrates another method of utilizing a cannula apparatus topenetrate through a patient's skin for deployment of an OSA implant in apatient's tongue.

FIG. 34 illustrates another method of utilizing a curved cannulaapparatus for deployment of an OSA implant in a patient's tongue.

FIG. 35A depicts another OSA implant that comprises a unitary V-shapedimplant body with first and second legs and anchoring ends implanted ina patient's tongue for applying linear-directed forces in differentdistinct vectors.

FIG. 35B depicts first and second OSA implants that utilize a fibroticresponse to effectively create in-situ a V-type implant with first andsecond legs for applying linear-directed forces in different vectors.

FIG. 36 depicts another OSA implant that is configured with an elementof an anchoring end portion configured for extending transverse to theaxis of contractile muscle fibers.

FIG. 37 illustrates another OSA implant that includes an elongatedelastic portion and cooperating elongated bioerodible portion fortemporarily maintaining the implant in an extended, stressed position.

FIG. 38A illustrates an OSA implant that has a curved configuration thatcan allow the tongue to move by straightening the implant.

FIG. 38B depicts the curved implant of FIG. 38A in a straightened shapewith the tongue displaced posteriorly toward obstructing the airway.

FIG. 39 depicts a curved implant as in FIG. 38A implanted in ahorizontal plane in the patient's tongue.

FIG. 40A depicts an S-shaped or serpentine implant in a verticalorientation that may allow the tongue to move by straightening theelastic implant.

FIG. 40B depicts the serpentine implant of FIG. 40A in a straightenedshape with tongue displaced posteriorly.

FIG. 41 depicts a helical curved implant that again can allow the tongueto move by straightening the implant.

FIG. 42 depicts another type of implant that comprises a loop orencircling OSA implant with a connection means adjacent first and secondends thereof, the implant in a vertical orientation in a patient'stongue.

FIG. 43 depicts an encircling implant as in of FIG. 41 in horizontalorientation in a patient's tongue.

FIG. 44A depicts a device configured for implanting the encirclingimplant of FIGS. 42-43, with first and second trocar elements and aguide block.

FIGS. 44B-44E depict schematically the steps of using the working end ofthe device of FIG. 44A to implant and deploy an encircling implant intissue.

FIGS. 44F-44G depict an encircling implant fully bridged between firstand second trocars; FIG. 44G depicts the trocar system proximate thepatient with the trocars being withdrawn, leaving the implant in place.

FIG. 44H depicts the final step of the method comprising fixedlyconnecting the two ends of the implant so as to form a loop orencircling implant.

FIG. 45 depicts various shapes of loop or encircling implants.

FIG. 46 depicts a loop or encircling implant with its ends fixedlyconnected around the geniohyoid muscle to serve as an anchor.

FIG. 47 depicts a U- or V-shaped implant with two anchors in theanterior position, adjacent to the mandible.

FIG. 48 illustrates a V-shaped implant with two anchors at the distalends that are the legs of the V-shape in a horizontal orientation in apatient's tongue.

FIG. 49 illustrates a V-shaped implant with two anchors at the distalends that are the legs of the V-shape in a vertical orientation in apatient's tongue.

FIG. 50A depicts a device and first step of a method for implanting theV-shaped implant of FIG. 48 in a patient's tongue, wherein two curvedtunnelers form pockets for the legs of the V-shaped implant.

FIG. 50B depicts a subsequent step of the method wherein the tunnelersare removed, and two curved push rods with hooks at the distal endsthereof pushing or maintain the anchor ends of the implant in place.

FIG. 50C depicts the patient's tongue after the trocar is withdrawnleaving the V-shaped implant in its final position.

FIG. 51 depicts a V-shaped implant as in FIG. 50C anchored around thegeniohyoid muscle.

FIG. 52 depicts a combination implant with an encircling portionanchored around the geniohyoid muscle and a linear portion with ananchoring end near the tongue base.

FIG. 53 depicts an elongated implant body having an elastomeric medialportion and a large planar end implanted in a tongue.

FIG. 54 depicts an elongated implant body having an intermediate releasemechanism in the medial portion.

DETAILED DESCRIPTION A. Anatomy of the Pharynx

FIG. 1 is a sagittal view of the structures that form the pharyngealairway 4; some of these structures can become compromised under variousconditions to the extent that they obstruct or occlude passage of airthrough the airway 4, and thus contribute to obstructive sleep apnea.The pharynx is divided, from superior to inferior, into the nasopharynx1, the oropharynx 2 and the hypopharynx 3. Variations of FIG. 1 areprovided in FIGS. 2A and 2B which depict airway obstruction sites 5 atvarious levels in the pharyngeal airway. FIG. 2A, for example, shows anocclusion 5 at the level of the oropharynx 2, where the base of thetongue 16 and a thickened posterior pharyngeal wall 22 have collapsedagainst each other. FIG. 2B provides a view of a compromised airway withpalate closure. It is also possible for airway obstruction to occur atthe level of the nasopharynx 1, where an elongated and/or floppy softpalate can collapse against a thickened posterior pharyngeal wall.Further, an obstruction can occur at the level of the hypopharynx 3,where both an elongated soft palate and a floppy epiglottis 12 cancollapse against the pharyngeal wall 22.

With reference to FIGS. 1-2B, the nasopharynx is the portion of thepharynx at the level or above the soft palate 6. In the nasopharynx, adeviated nasal septum or enlarged nasal turbinates may occasionallycontribute to upper airway resistance or blockage. Rarely, a nasal mass,such as a polyp, cyst or tumor may be a source of obstruction. Theoropharynx 2 includes structures from the soft palate 6 to the upperborder of the epiglottis 12 and includes the inferior surface of thehard palate 14, tongue 16, posterior pharyngeal wall 22 and the mandible24 as well as the tonsils and palatoglossal arch. The mandible typicallyhas a bone thickness of about 5 mm to about 10 mm anteriorly withsimilar thicknesses laterally. An obstruction in the oropharynx 2 mayresult when the tongue 16 is displaced posteriorly during sleep as aconsequence of reduced muscle activity during deep or non-REM sleep. Thedisplaced tongue 16 may push the soft palate 6 posteriorly and may sealoff the nasopharynx 1 from the oropharynx 2. The tongue 16 may alsocontact the posterior pharyngeal wall 22, which causes further airwayobstruction.

The hypopharynx 3 includes the region from the upper border of theepiglottis 12 to the inferior border of the cricoid cartilage. Thehypopharynx 3 further includes the hyoid bone 28, a U-shaped,free-floating bone that does not articulate with any other bone. Thehyoid bone 28 is attached to surrounding structures by various musclesand connective tissues. The hyoid bone 28 lies inferior to the tongue 16and superior to the thyroid cartilage 30. A thyrohyoid membrane and athyrohyoid muscle attach to the inferior border of the hyoid 28 and thesuperior border of the thyroid cartilage 30. The epiglottis 12 isinfero-posterior to the hyoid bone 28 and attaches to the hyoid bone bya median hyoepiglottic ligament. The hyoid bone attaches anteriorly tothe infero-posterior aspect of the mandible 24 by the geniohyoid muscle.Below the hypopharynx 3, the trachea 32 and esophagus 34 are also shown.

B. Revisable OSA Implants

FIG. 3A depicts a first component in an exemplary embodiment of a kit orsystem that provides revisable implants for treating an airway disordersor obstructive sleep apnea (OSA). The second component of the exemplarykit is an introducer for insertion into a treatment site as is known inthe art and co-pending applications. In FIG. 3A, an elongate device orimplant body 100A has first and second end portions 105A and 105B withthrough-openings 106A and 106B therein. The medial portion 110 of theimplant body 100A extends along axis 111 and comprises a biocompatibleelastomeric material such as a silicone. The mean cross-section of themedial body portion 110 can range from 1 to 10 mm² and can be round,oval, flat, polygonal or other suitable shapes. In some embodiments, theelastic modulus of the medial portion can range from 0.5 to 10 MPA andis configured for implanting in the patient's airway tissue in areleasable, tensioned position, as described in co-pending U.S. patentapplication Ser. No. 11/969,201 which is incorporated herein by thisreference.

Referring to FIGS. 3A and 3B, it can be seen that through-openings 106Aand 106B in the implant body 100A are configured for growth of a tissueplug 112 through the opening to thereby secure the first and second endportions 105A and 105B in a selected tissue site. The cut-away view ofFIG. 3B schematically illustrates that a tissue plug 112 that growsthrough the opening is thus surrounded or encircled by an encirclingbody portion 115 of the implant. The encircling body portion 115comprises a small cross-section element that can be cut, severed,sacrificed, decoupled, or dissolved to disengage the implant from atissue site 120 as will be described below. The element can be a polymeror other material. In other embodiments described below, the tissue plug112 can be cut or severed to disengage the implant from the tissue site120. In one embodiment, the mean cross-section of the tissue plug 112,and thus the dimension across an opening 106A or 106B, can range fromabout 0.5 mm to 10 mm or more. The openings 106A or 106B can have around shape in plan view or any other plan shape. The end portions 105Aand 105B can have similar or dissimilar configurations, for example animplant configured for treatment of a patient's tongue may have asubstantially larger end portion and opening 106B for the base of thetongue and a smaller end portion near the mandible.

FIG. 3C illustrates another implant body 100B with an end portion 105Bhaving an elongated opening 106B through which tissue will grow to forma tissue plug to secure the end portion in the site. For example, theimplant body 100B of FIG. 3C has an opening 106B with a primary axis 121and larger dimension that extends generally orthogonal to the axis 111of medial portion 110 of the implant body. In use, the greater dimensionof the tissue plug will better resist the retraction forces applied totissue by the elastomeric medial portion 110 of the implant aligned withaxis 111.

FIG. 3D depicts another embodiment 100C of a revisable implant fortreating an airway disorder that is similar to that of FIG. 3C exceptthe end portion 105B has a through-opening 106B with a terminal part 126of encircling portion 115 configured with irregular shaped surfacefeatures 128 that can interface with the tissue plug that grows throughopening 106B. The surface features can comprise undulations, textures,protrusions, bumps and the like that can assist in maintaining the endportion in a fixed position when under the tensioning or retractionforces applied by the medial portion 110 of the implant body 100C. Inthe implant body 100C of FIG. 3D, the end portion 105B also can have anencircling element 115 that includes a proximal portion 130 of a lowermodulus material similar to the modulus of medial portion 110 and theterminal part 126 having a higher modulus to prevent its deformationunder tensioning forces.

FIG. 4 depicts another embodiment 100D of a revisable implant that issimilar to previous embodiments except that at least one end portion105B includes an indent feature 140 in the proximal-facing aspect of theencircling portion 115 wherein the indent feature 140 is adapted todirect and receive a cutting blade or edge 144 (phantom view) of acutting tool for cutting the encircling portion of the implant body toallow its removal from the treatment site. As will be described below(with reference to FIG. 5B), a cutting tool 145 can be advanced alongthe medial portion 110 of the implant to sever the end portion, whichthen will allow the entire implant to be withdrawn from the implantsite. In another aspect of the invention, the indent feature 140 in theencircling portion 115 can direct the cutting edge 144 to a reducedcross section portion 148 that will require limited force to cut thepolymer element with the cutting edge 144.

FIGS. 5A and 5B illustrate a second component of an exemplary kit of arevisable OSA implant system wherein the tool 145 comprises an elongatemember with a distal cutting edge 144. One tool embodiment has apassageway 152 extending therethrough for receiving the elongate implantbody 100D. In using this tool 145, a first end of the implant body wouldbe freed from tissue or cut and then threaded through the passageway152. Thereafter, as depicted in FIG. 5B, the tool 145 can be advanceddistally while holding the proximal end of the implant to cause thecutting edge 144 to cut across the encircling portion 115. In FIG. 5B,it can be understood how the indent feature 140 and reduced crosssection portion 148 (see FIG. 4) direct the cutting edge 144 to easilycut the element to thus release the implant from encircling the tissueplug 112 (cf. FIG. 3B). The tool 145 can be a rigid or semi-rigid membersuch as a hypotube with a sharpened end. The tool also can be adeflectable, articulatable or steerable member as is known in the art.In another embodiment, the tool can be a flexible plastic material witha blade insert to provide the cutting edge 144. Referring to FIGS. 5Band 3B, it can be understood that the cut end is flexible and can bepulled from around the tissue plug to extract the implant from the site120 (see FIG. 3B).

FIG. 6 illustrates another second tool component of a revisable implantsystem wherein the tool 145′ again comprises an elongate member with adistal cutting edge 144.

In one embodiment, the tool end includes a longitudinal gap 155 along aside of passageway 152 to thus allow the tool to be inserted over medialportion 110 of an implant body to then advance and cut the implant asdepicted schematically in FIGS. 5A-5B. The tool end as shown in FIG. 6can comprise a polymer member with flexible elements 158 on either sideof gap 155 to allow gap 155 to flex open when the device is beinginserted over the implant. As depicted, distal cutting edge 144 maycomprise a metal blade insert 160 molded into a polymer member.

FIGS. 7A-7C illustrate other embodiments of implants 200A, 200B and 200Cthat each has a plurality of the through-openings 206 in variousconfigurations. In these embodiments, the ends are flat or planar withthe openings therein. Thus, in use, there will be a plurality of tissueplugs that grow through the openings to secure the implant ends in thetissue site.

FIG. 7D illustrates another embodiment of implant 200D that has anon-planar end 201 with a plurality of through-openings 202. In oneembodiment, the ends have a plurality of elements 204 that extend indifferent radial angles relative to the axis 111 of the implant witheach such element 204 having one or more openings therein.

FIG. 7E illustrates an implant body 200E with ends 205A and 205B andmedial portion 206 that comprises an axially-stretched and tensionedelastomeric material. The medial portion 206 is releasably andtemporarily maintained in the axially-stretched non-repose condition bya biodissolvable portion, such as of magnesium or magnesium alloy,indicated at 208. In this embodiment, the biodissolvable portion cancomprise a tubular member with a foil-like wall or thin-wall, aplurality of thin-wall tube segments, or one or more windings or braidsof biodissolvable material. The thin-wall material can be perforated asshown in FIG. 7E. The thin-wall biodissolvable material, or thebiodissolvable filament of a winding or braid, can be very fine andadapted to dissolve, erode and/or absorb into the body with a selectedtime interval ranging from about 2 weeks to 52 weeks. In anotherembodiment, the biodissolvable portion can be disposed in an interiorportion of the implant body, in a linear or helical configuration.

FIG. 8A depicts the working end 210 of an elongated tool that is adaptedfor cutting an end portion of an implant for its removal, for example animplant of FIG. 3A-3D, 4, or 7A-7D. The tool functions similar to thatof FIGS. 5A and 6, wherein the tool has a central bore 212 that receivesthe elongate medial portion of an implant body. As can be seen in FIG.8A, the working end 210 includes two concentric hypotubes with a notch214 therein to push over an end portion 115 of implant 100A of FIG. 3A,for example. The physician can counter-rotate the hypotubes from aproximal handle end wherein blade edges 215 and 216 of the working endfunction as a scissors mechanism to cut the implant body. Thereafter,the implant can be easily removed from the treatment site. FIG. 8Billustrates another working end 210′ of a similar cutting tool that hasopposing notches 214 and 214′ that can receive a implant body portionand blade edges 215 and 216 can be rotated to cut the implant.

FIG. 9 illustrates another embodiment of implant 220 that is similar toany previous embodiment except depicting a difference in surfacecharacteristics of the implant. The end or encircling portion 225 mayhave smooth or slightly textured surface features and the medial portion230 may comprise a highly lubricious surface, such as an elastomericmaterial having an ultra-hydrophobic surface 232 to allow for slippageof the tissue against the implant during use. Thus, a method of theinvention comprises implanting a device in airway-interface tissue,securing first and second implant end portions in the tissue bypermitting a tissue growth through at least one opening in an endportion, and allowing an elastomeric portion of the implant to applyretraction forces to alleviate tissue obstruction of the airway whereinan ultrahydrophobic surface of the implant prevents tissue adhesion tosaid surface. Ultrahydrophobic surfaces can be provided in abiocompatible polymer, as is known in the art.

In another aspect of the invention, referring to FIG. 9, the elongateimplant body is configured for implanting in an airway-interface and atleast a portion of a body surface has a wetting contact angle greaterthan 70°, to prevent tissue adhesion and to allow tissue slippage. Inother embodiments, at least a portion of a body surface has a wettingcontact angle greater than 85°, or greater than 100°.

In another aspect of the invention, still referring to FIG. 9, theelongate implant body is configured for implanting in anairway-interface and at least a portion of a body surface has anadhesive energy of less than 100 dynes/cm, less than 75 dynes/cm or lessthan 50 dynes/cm.

FIG. 10 illustrates another embodiment of revisable OSA implant 250similar to previous embodiments except the medial portion 252 includes apassageway 254 configured for extending a cutting tool 255 through thepassageway for cutting a distal end portion 258 of the implant. Thepassageway 254 can be accessed by an access opening in the opposing end(not shown) that can be identified by imaging of a marker, visualobservation of a marker, by a left-in place guidewire or other suitablemeans or mechanism. The cutting tool 255 can comprise a scissor member,an extendable blade that is extendable from a blunt-tipped tool, anydistal or proximally-facing blade, and/or any type of thermal energyemitter adapted for cutting the implant end 258.

FIG. 11 illustrates another embodiment of revisable OSA implant 280 thathas a sacrificial portion indicated at 282 that can be severed orsacrificed by an external stimulus. In one embodiment, a medial portion283 of the implant includes electrical contacts or extending leads 284Aand 284B that can be detachably coupled to an electrical source 285. InFIG. 11, the implant body comprises an elastomeric material as describedabove and the sacrificial portion 282 comprises a conductively dopedpolymer portion that acts as a fuse when subject to a very short burstof high voltage RF current. Opposing sides or aspects of the sacrificialportion 282 are coupled to electrical leads 288A and 288B that areembedded or molded into the implant. The use of such doped polymers fora fuse-effect for detachment of endovascular medical implants isdisclosed in U.S. Pat. No. 6,458,127 to Truckai et al and issued Oct. 1,2002, which is incorporated herein by reference. Similar doped polymerscan be used in the revisable OSA implant of FIG. 11.

FIG. 12 illustrates a method of using the OSA implant 280 of FIG. 11,and more particularly for revising the treatment. FIG. 12 depicts thatan RF current from source 285 has been delivered to melt, sever andsacrifice portion 282 of the implant thus allowing extraction of theimplant from around the tissue plug.

FIGS. 13A and 13B illustrate another embodiment of revisable OSA implant290 that has a sacrificial portion indicated at 282 in a medial portionof the implant that can be actuated and sacrificed by the externalstimulus which then leaves the encircling portion 115 of the implant inplace. The left-in-place portion of the implant can be used as an anchorfor subsequent implants. In one embodiment as in FIGS. 13A-13B, thesacrificial portion 282 can comprise an electrolytic wire that can besacrificed over a short time interval by direct current as is known inthe art. Such electrolytic wire for detachment of embolic coil implantsare known in the field of aneurysm implants and treatments.

While FIGS. 11-13B show OSA implants with two forms of sacrificialportions, it should be appreciated that similar implants can havesacrificial portions that are cut, severed or sacrificed by any externalstimulus such as RF current, DC current, light energy, inductive heatingetc. and may fall within the scope of aspects of the invention.

FIGS. 14 and 15 illustrate another embodiment of revisable OSA implant300 that again includes at least one end with an encircling portionindicated at 315 that encircles a tissue plug 316 that grows through anopening 320. In one embodiment, the implant carries a cut wire 322 thatextends in a loop with first and second wire ends 324A and 324Bextending through one or more passageways in the implant. The cut wire322 can be embedded in the surface of the implant surrounding theopening 320. As can be seen in FIG. 15, the looped cut wire 322 can bepulled proximally to cut the tissue plug 316 which then will free theimplant from its attachment. In FIG. 14, it can be seen that the cutwire ends 324A and 324B can have a serpentine configuration in themedial portion of the implant so as to not interfere with the tensioningand relaxation of the elastomeric medial implant portion during its use.When the cut wire is accessed and pulled relative to the implant 300,the tissue plug 316 can be cut. It should be appreciated that othertools (not shown) may be used to stabilize the implant when actuatingthe cut wire as in FIG. 15. The cut wire 322 can be any form of finewire, or abrasive wire or a resistively heated wire coupled to anelectrical source (not shown).

FIG. 16 depicts another revisable OSA implant 300′ that is similar tothat of FIGS. 14-15 with the cut wire 322′ configured to cut a pluralityof tissue plugs 316 that have grown through openings 320 within anencircling end portion of the implant body.

FIG. 17 depicts another OSA implant 400 that is adapted for revision asprevious implants and systems wherein the elongate device or implantbody has first and second end portions 405A and 405B withthrough-openings 406A and 406B therein. The medial portion 411 ofimplant body 400 extends about an axis and comprises a biocompatibleelastomeric material such as a silicone. In this embodiment, the medialportion comprises first and second extending portions 415A and 415Bwherein one such portion can be nested in a passageway 416 of the otherportion and then form proximal and distal loops or encircling endportions that define openings 406A and 406B for receiving tissue plugstherein. As can be understood from FIGS. 17 and 18A, both the extendingportions 415A and 415B comprise an elastomeric material and thus combineto provide the desired retraction forces of the OSA implant.

Referring to FIGS. 18A and 18B, it can be seen that if the secondextending portion 415B is cut in a medial or proximal aspect of theimplant, or if both the first and second extending portions 415A and415B are cut in a proximal or medial aspect, then a proximal aspect ofthe first or outer extending portion 415A can be pulled in the proximaldirection and the cut second extending portion 415B then will snake outof the path around the tissue plug 422. Thus, the implant can be cut ina proximal or medial aspect and can be withdrawn from the treatment sitefrom a remote access location.

FIG. 19 depicts another OSA implant 450 that is adapted for a revisionprocedure and comprises an elongate implant body with first and secondend portions 455A and 455B with through-openings 456A and 456B therein.This embodiment is similar to that of FIG. 17 in that medial portion 458includes extending portions 460A and 460B comprising an elastomericmaterial that combine to provide the desired retraction forces of theOSA implant. The extending portions 460A and 460B are carried in a thinelastomeric sleeve 464 that has tear-away portions 465 about its ends toprevent tissue ingrowth into the passageway in the sleeve. It can beunderstood that by cutting the medial portion of the implant, and thenpulling on an end of an extending portion 460A or 460B will cause theother free end of the implant to snake around the tissue plug similar tothe method depicted in FIG. 18B. Both ends of the implant can be removedfrom the treatment site by this method.

C. In-Situ Adjustable Force OSA Implants

Another type of OSA implant includes means for in-situ adjustment offorce applied by the implant after implantation in the treatment site.Such an adjustment can increase or decrease the applied forces appliedto the treatment site by the implant. Such adjustment of forces appliedby the implant typically may be performed upon specific event, such asperiodic evaluations of the treatment. The adjustment also can be doneat a pre-determined schedule, based on an algorithm, or can be random.In one example, the patient may gain or lose weight which could resultin a need for adjusting the forces applied by the implant. Otherinfluences can be a worsening of the patient's condition, the aging ofthe patient, local tissue remodeling around the implant, age of theimplant or degradation of material properties of the implant. In someembodiments described below, an implant system can be provided that iseasily adjustable in-situ between first and second conditions on arepetitive basis, for example, that can be adjusted for sleep intervaland for awake intervals on a daily basis. Such an adjustable embodimentcan thus deliver tissue-retraction forces only when needed during sleep.One advantage of such an embodiment would be to allow the tissue of thetreatment site to be free from implant-generated retraction forcesduring awake intervals to prevent or greatly limit the potential oftissue remodeling due to a continuous application of such retractionforce.

FIG. 20 depicts a revisable OSA implant 500 that is adapted forminimally invasive in-situ post-implant adjustment of retraction forcesapplied by the implant. In this embodiment, the implant is configuredfor a downward adjustment of retraction forces applied by the OSAimplant. In FIG. 20, it can be seen that the elongate implant body has aplurality of extending elements 502 coupled to end portion 505, whereinthe elements 502 can be individually cut to reduce the appliedretraction forces of the implant. The number of extending elements 502can range from 2 to 20 or more.

FIG. 21 depicts a revisable OSA implant 520 that functions as theprevious embodiment except that the plurality of extending elements 502are housed in thin-wall elastomeric sleeve 522. Further, an axialportion 525 of some or each extension element 502 protrudes outward fromsleeve 522, or an end portion 530 of the implant, to allow such aportion to be cut. Soft filler or “tear away” material 532, such as avery low modulus silicone, may be provided around each extension element502 where it protrudes from sleeve 522 to prevent tissue ingrowth intothe interior channels of the device. In use, a physician is able to pickup the elastic element 502 and cut it, and filler material 532 justtears away in the process. Again, any form of cutting tool can be usedfor minimally invasive access to cut an elastomeric element to titrateretraction forces in a downward direction.

FIG. 22 depicts an OSA implant 600 that is adapted for in-situpost-implant adjustment of retraction forces applied to targeted tissue.In one method, assume that it is desirable to increase the appliedretraction forces over time due to tissue remodeling wherein greaterretraction forces are desired. In FIG. 22, the elongated implant bodyhas a medial portion 606 that includes an interior channel 610 thatextends from an accessible first end 612 to a remote end 615. Each end612 and 615 can include a silicone membrane to prevent tissue ingrowthbut will allow a needle to be inserted therethrough. The channel ends612 and 615 can be disposed in more rigid end portions of the implant,wherein the medial portion of the implant body comprises an elastomer toprovide the desired retraction forces. In one embodiment, the channel610 is dimensioned to collapse or flatten but can also accommodate theinsertion of at least one additional elastomeric element indicated at620. It can be understood from FIG. 23 that an elastomeric element 620with end-toggles 624 be inserted in a bore of a flexible needle member(not shown) and inserted through the channel in the implant so that thetoggles are released to deploy the element 620 in a tensioned positionto thereby add to the retraction forces applied to tissue collectivelywith the medial portion 606 of the implant 600. In a similar manner, anend of the implant 600 and/or elastomeric element 620 can be clipped toreduce the applied retraction forces as in the system and methoddepicted in FIGS. 20 and 21.

Thus, in general, the system and implants of FIGS. 20-23 correspondingto aspects of the invention comprise an elongate implant sized andshaped to conform to an airway-interface tissue site in a mannercompatible with normal physiological function of the site, a medialportion of the implant comprising an elastomeric material configured toapply retraction forces to the site, and adjustment means for in situadjustment of retraction forces applied by the implant.

D. OSA Implants for Applying Non-Aligned Displacement Forces

Another aspect of the invention can be described with reference to FIG.24-27, wherein a resilient implant (or implants) can be positioned inairway-interface tissue to apply tensile forces or displacement forcesin at least two non-aligned or separate directions or vectors. These canbe referred to as distinguishable vectors. In a typical embodimentdepicted in FIGS. 24-25, an implant 700 corresponding to aspects of theinvention can form a linear structure wherein two anchor ends 702 a and702 b form anchor points or regions 705 a and 705 b in the tissue. Suchpoints 705 a and 705 b are connected by a straight or substantiallystraight elastic portion 710 or spring element of the implant such thatsaid elastic portion or spring element applies a tensile force and/or atensile displacement between said anchor points 705 a and 705 b. In theembodiment of FIG. 24, the implant 700 acts to apply forces and/ordisplacements between the said anchor points 705 a and 705 b to displaceand/or apply forces to the patient's tongue, but it should beappreciated that an appropriately dimensioned implant can also orinstead be introduced into the soft palate or pharyngeal structuresadjacent to the patient's airway. FIG. 25 illustrates the implant 700can have various orientations in the tissue. Now turning to FIGS. 26-27,it can be seen that a plurality of substantially linear elastic implants700 similar to that of FIGS. 24-25 can thus provide a plurality oftissue anchor points 715 wherein the elastic or spring portion 710 ofthe implants function in such a manner to provide tensile ordisplacement forces to achieve the desired clinical effects. Testing inanimal models has indicated that forces applied to the subject's tongueby two implants in two different directions may improve implantperformance when compared with unidirectional application of forces froma single implant.

FIGS. 28A-28C schematically illustrate another embodiment of implantsystem according to aspects of the invention that comprises first andsecond elastic elements 720A and 720B that provide three anchor pointsin tissue indicated at 725 a, 725 b and 725 c. FIG. 28A depicts theimplantation of the first elastic element 720A which has anchoring ends728 a and 728 b as described above, wherein at least one end isconfigured with an attachment element such as a loop 730 that isconnectable with a hook element 732 of a second elastic element 720B.Thus, FIGS. 28A and 28B depict the steps of implanting the elasticelements, wherein elastic element 720A is initially implanted in itsdesired location as shown in FIG. 28A. Then, FIG. 28B depicts elasticelement 720B being positioned in its desired location such that the hook732 is adjacent to loop 730 of the elastic element 720A. FIG. 28C thendepicts the loop 730 and hook 732 be connected in such a manner so as toproduce a fixed-link implant structure which thus applies forces in twonon-aligned vectors AA and BB. It can be understood that the implantscan be implanted in sequence and then coupled in situ to form a V-shapedimplant system. It should be appreciated that the implant structure ofFIGS. 28A-28C can have components such as elastic or spring elementsthat can be connected prior to, during, or following implantation bymeans of adhesives, connectors, snap-fit features, hooks and loops,clamps, ratchets, keyed fittings, etc., or by means of separateattachment, such as sutures, junctions, clamps, or other connectionmeans. In another embodiment, two end portions of separate implantbodies can be disposed proximate to one another, and the body's fibroticresponse or wound healing response can cause a connection of the twoimplant ends.

FIGS. 29A-29B schematically illustrate another embodiment of implantsystem comprising first and second elastic elements 740A and 740B in adifferent orientation in a patient's tongue. Each implant has an elasticmedial section as described above. The implant system again providesthree anchor points 745 a-745 c as shown in FIG. 29B, wherein the firstimplant can be fixedly attached to the second implant by loop and hookfeatures or other similar means. As described previously, the implantscan be implanted in sequence and then coupled in situ to form theV-shaped implant system. In some embodiments, the angle between the legsof the V-shaped implant ranges from about 10° to about 90° depending onthe implant site. In other embodiments, the angle between the legs ofthe V-shaped implant ranges from about 10° to about 170°. The lengths ofthe legs of the V-shaped implant can vary, as well as the forces appliedby each leg of the V-shaped implant.

In general, when the implants of the disclosure as described above areimplanted in the tongue and/or the palate of the patient (FIG. 35), thepositioning of the implants will affect the location and direction ofthe applied forces and the displacements of the surrounding tissues. Theimplants may be placed in various locations to achieve the desiredclinical effects, and may be specifically tailored to an individualpatient based on the nature and details of each patient's OSA, includingtheir specific anatomy and physiology. For example, if a patient suffersobstructions associated with the lower posterior region of the tongueimpinging on the posterior pharyngeal wall, then an implantationlocation that places one end of a linear implant lower in the tongue maybe appropriate (see FIG. 24). In another example, if the patient suffersobstructions associated with the upper posterior region of the tongueimpinging on the posterior pharyngeal wall, then an implantationlocation that places one end of a linear implant higher in the tonguemay be more appropriate (see FIG. 25). In a similar manner, the implantsof the disclosure may be placed in various locations within the tongueand soft palate, utilizing one or more implants, to address the specificneeds of the patient and to achieve the desired clinical effects.

In general, a method according to aspects of the invention for treatingan airway disorder comprises implanting at least one elastic implant inairway-interface tissue wherein the at least one implant is configuredto apply tensile forces to the tissue in at least two non-aligneddirections or vectors. The non-aligned vectors thus describe thelinearly-directed forces applied to tissue by substantially linear,elongated implants disposed in the tissue, such as vectors AA and BB inFIG. 28C.

In one aspect of the method, the linearly-directed forces can be appliedto tissue in the non-aligned vectors by a single implant configured withfirst and second body portions that extend in-between differentanchoring sites (see FIG. 35). In another aspect of the method, at leastfirst and second implants can be implanted to apply such forces in atleast first and second non-aligned vectors. In any implant embodiment,the elongated elastic body portions can cooperate with bioreodiblematerials that temporarily maintain the implant in an extended positionas described above. Further, as described previously, the targetedairway-interface tissue which receives the implant can comprise thepatient's tongue, soft palate and/or pharyngeal tissue.

Now turning to FIGS. 30-34, various aspects of the invention aredescribed that relate to placement of the implants within the tongue orsoft palate of the patient. Implantation may be achieved in a variety ofmanners, and typically is accomplished by the insertion of aneedle-based cannula 760 as shown schematically in FIG. 30. It should beappreciated that an open surgery or other minimally invasive surgicaltechnique can be used. In one embodiment of sharp-tipped cannula 760shown in FIG. 31, the implant body 770 is carried in bore 772 of thecannula. A thin push rod or stylette member 775 has a distal end 777that releaseably engages a distal portion 778 of the implant body. Theengagement can comprise a hook or other attachment means for couplingwith the distal end of the implant body. The stylette 775 can reside inthe cannula bore 772 alongside the flexible implant body in such amanner that when said stylette is pushed, the distal end of the stylettefunctions to pull or deploy the implant 770 through said cannula,avoiding any jamming or bunching of said implant during deployment.Further, the implant can be deployed in the targeted tissue site in afully elongated (i.e. non-bunched) fashion. In another aspect of themethod, the cannula is introduced into the targeted site, and thereafterthe physician maintains the stylette 775 in a fixed position andcontemporaneously withdraws the cannula 760 to thus deploy the implantbody 770 in the targeted site.

The disclosed implants may be placed within the tongue by means ofstraight, curved, articulating, deformable and/or telescoping cannulas760 as in FIGS. 30-34, which may be introduced through any access pointsdescribed above. The route of access to the implantation site within thetongue may include access via a sublingual location as depicted in FIGS.30 and 32A-32B, (within the oral cavity, below the anterior portion ofthe tongue), access via a submandibular location as depicted in FIGS.33-34 (below the anterior portion of the mandible), access via aposterior lingual location (on the posterior surface of the tongue) orany other access point that may allow for proper implant positioning.

The route of access to the implantation site within the soft palate mayinclude access via an intra-oral location (within the oral cavityadjacent to the junction of the soft palate and the hard palate) or anintra-nasal location (within the nasal cavity adjacent to the junctionof the soft palate and the hard palate), or any other access point alongthe soft or hard palate that may allow for proper implant positioning.

In one example, FIG. 30 shows a straight cannula inserted in thesublingual location, resulting in a substantially straight placementwith the anterior anchor located adjacent to a superior part of themandible. In another example, FIGS. 32A-32B depict an angled, bendable,or articulating cannula 780 with a telescoping secondary cannula 782inserted in the sublingual location which would result in asubstantially straight implant placed with the anterior anchor portionof the implant located adjacent to a superior part of the mandible.

FIG. 33 depicts a straight cannula 760 inserted in the submandibularlocation which would result in a substantially straight implantplacement with the anterior anchor located adjacent to an inferior partof the mandible. In another example, FIG. 34 shows a curved cannulainserted from a submandibular location which results in a slightlycurved placement with the anterior anchor located adjacent to amid-level position on the mandible.

In another embodiment, the second sleeve may have memory shape (e.g.NiTi) or may be a plastic sleeve.

The disclosed implants as described above are substantially flexible,and are typically fabricated of flexible and/or elastic materials suchas silicone, urethane, fluoroelastomer, or other bio-compatibleelastomers, polyethylene terephthalate (e.g. Dacron®) or other fibers,bioabsorbable polymers, flexible metals or the like. The flexibility ofthe implants allows for such implants to be easily deployed andimplanted through small cross-section cannulas, which may be straight,curved or articulated, without the implant body jamming within thecannula bore. Longer implants may be delivered through curved or bentcannulas than would be possible with stiff or rigid implant materials ordesigns.

Because such implants are substantially flexible, pulling the implants,instead of pushing them, through the cannulas may be advantageous forcertain applications, such as narrow, straight, curved, deformable orarticulated cannulas. The primary advantage of pulling or deploying aflexible implant from such a curved or straight cannula is an increasedresistance to bunching, buckling, or otherwise jamming in the cannulabore. This aspect of the deployment method allows such flexible implantsto be delivered around tight bends in the cannula, thus enablingimplantation in difficult to reach locations such as delivery within thetongue through the sublingual space (see FIGS. 31-32B). Pulling alsoallows longer implants to be delivered than would otherwise be the case.In another embodiment, only the end portions of the implant aredeformable.

FIG. 35A schematically illustrates another embodiment of implant 790that comprises a unitary implant body with first and second elasticelements (“legs”) 792A and 792B that can be deployed in differentorientations in different patients' tongues. It can be understood thatimplant 790 of FIG. 35A can be implanted by means of a primary cannulacarrying two resilient curved stylettes (or secondary slotted cannulas,not shown) that are deployed from the primary cannula. The implant 790again provides three anchor points 795 a-795 c as shown in FIG. 35. Asdescribed above, the V-shaped implant 790 can have any suitable anglebetween the legs 792A and 792B and any suitable forces can be applied byeach leg of the V-shaped implant.

FIG. 35B depicts first and second OSA implants 796A and 796B that areintroduced with at least a portion of the implants in close proximity.Thereafter, a fibrotic response indicated at 798 may be induced that caneffectively couple the ends of the implants to again provide a V-typeimplant wherein the first and second implants apply linear-directedforces in different vectors.

Exemplary implants of the disclosure can be configured with anchorportions at various locations along the implants, including the ends, ordistributed along the length of the elastic or spring elements of theimplant, or adjacent to the elastic or spring elements and serve toattach the implants to tissue. The tissue can comprise soft and hardtissues and structures, including skin, mucosa, muscle, fascia, tendon,ligament, cartilage, or bone so as to allow the elastic or springelements to apply forces and/or displacements to said soft tissue, hardtissues or structures. When employed within a patient's tongue, theanchor portions of such implants can form attachments directly withintongue muscles, including the geniohyoid, the genioglossus, thevertical, the transverse, and the longitudinal muscles. The geniohyoid,the genioglossus, and the vertical muscles within the tonguesubstantially run in a direction from their attachments at the centralanterior portion of the mandible and fan outward isentropically towardthe posterior and superior oral cavity where the transverse andlongitudinal muscles reside (FIG. 36). As described above, the anchorportion of the implant can attach by means of tissue plugs through holesin the anchor portions, ingrowth of muscle tissue into channels,passages, pores, or other interstitial spaces in the anchor portion ofthe implant body.

The implants of the disclosure may be implanted in such a manner and inspecific orientations so as to encourage the isentropic muscle tissue toin-grow and attach to said anchors to encourage specificcharacteristics. These characteristics may include, but are not limitedto, accelerated or delayed attachment to said muscle tissues, strongeror weaker attachments, isentropically strengthened attachments, reducedor increased stiffness of the attachments, reduced pain and/or reducedsensitivity of the attachments.

In another aspect of the invention, an implant 800 (FIG. 36) has endportions or anchoring portions 805A and 805B that are configured withelements, surfaces and surface areas that allow for tissue plugs ortissue growth therein that resist unwanted movement of the implant endwithin tissue planes, such as along the surface of muscle fibers 808.FIG. 36 depicts the orientation of muscle fibers 808 in a patient'stongue. More in particular, referring to FIG. 36, the implant 800 hasend portions 805A and 805B each with an element 810 that is configuredto extend transverse to a selected dimension of such muscle fibers 808.The length of the feature or element 810 that extends transverse tomuscle fibers can be at least 2 mm, 4 mm, 6 mm or 8 mm to therebyprovide assurance that the implant will not migrate in an intra-musclefiber tissue plane.

In another aspect of the invention one or more of the anchoring portioncan be a composite structure (e.g. a polyester fiber reinforced siliconerubber or a substantially non-elastic polymer or metal). The compositestructure may limit loss of applied force that might otherwise occur dueto stretching of the anchoring portion.

In another aspect of a method of the invention, referring to FIG. 36,the implant body 800 is positioned in a targeted site, such as apatient's tongue, such that the forces applied by the elastic portion ofthe implant are substantially aligned with the direction of contraction(or axis) of contractile muscle fibers 808 and wherein the anchoringportions of the implant body 800 include tissue engaging elements thatextend substantially transverse to the axis of such contractile musclefibers 808.

FIG. 37 illustrates another embodiment of flexible implant 820 which canbe temporarily maintained in an elongated position. In this embodiment,the implant 820 carries a semi-rigid rod 825 of a bioabsorbable material(e.g. a bioabsorbable polymer) embedded or locked into features on asurface of the implant body. The implant thus can be configured withsufficient buckling strength so that the implant 820 and bioabsorbablerod 825 can be pushed through a cannula that may be straight, bent,curved, or articulated, without jamming or bunching. This embodimentprovides an alternative means for implant deployment rather than thestylette deployment of FIG. 31.

E. Implant Force and/or Movement Parameters

Implant Force Threshold. The implants of the disclosure may apply forcesand displacements to anatomical structures within the patient's airway,including the tongue and soft palate, to treat obstructive sleep apnea(OSA) by repositioning and/or applying forces to said anatomicalstructures in such a manner as to provide an open airway during normalbreathing. The forces applied by said implants to said anatomicalstructures are large enough to sufficiently move, or displace, saidstructure so as to provide a clear airway when the patient is asleep,but are not so large as to damage the surrounding tissue, damage theimplant, prevent proper airway function, or prevent proper tonguefunction such as in normal speech and swallowing.

When the one or more implants of the disclosure are employed within thepatient's tongue to prevent airway occlusion associated with OSA whensaid patient is asleep and fully relaxed, said implant(s) providesufficient force to allow the airway to open during normal breathing.The force necessary to open said airway during normal breathing may be aforce less than the weight of the tongue itself, as normal breathingprovides an internal pressure that acts to help open the airway. Theminimum force supplied by said implant(s) to allow the airway to openduring normal breathing is referred to as the minimum threshold forcefor therapeutic benefit. This minimum threshold force for one or moreimplants within or adjacent to the tongue is about 0.5 Newtons in someembodiments, the minimum threshold force is about 1.5 Newtons in otherembodiments, and the minimum threshold force is about 3.5 Newtons instill other embodiments.

When one or more implants of the disclosure are employed within thepatient's soft palate to prevent airway occlusion associated with OSAwhen said patient is asleep and fully relaxed, said implant(s) providesufficient force to deflect the soft palate away from the back wall ofsaid patient's throat thus providing an open airway. As with the tongue,the force necessary to open said airway during normal breathing may be aforce less than the weight of the soft palate itself, as normalbreathing provides an internal pressure that acts to help open theairway. The minimum force supplied by said implant(s) to allow theairway to open during normal breathing is referred to as the minimumthreshold force for therapeutic benefit. This minimum threshold forcefor one or a more implants within or adjacent to the soft palate isabout 0.2 Newtons in some embodiments, the minimum threshold force isabout 0.5 Newtons in other embodiments, and the minimum threshold forceis about 1.0 Newtons in still other embodiments.

Implant Motion Threshold. The implants of the disclosure apply forcesand displacements to anatomical structures within the patient's airway,including the tongue and soft palate, to prevent obstructive sleep apnea(OSA) by repositioning said anatomical structures. The displacementsapplied by said implants to said anatomical structures are large enoughto sufficiently move, or displace, said structures so as to provide aclear airway when the patient is asleep, but are not so large as tocause adverse side effects. Said side effects may include limited tongueor soft palate function resulting in adverse effects on speech and/orswallowing, difficulty breathing, unwanted remodeling of tissues overtime, damage to soft or hard tissues, and causing said soft structures,like the tongue or soft palate, to interfere with other anatomicalstructures or to cause other unwanted effects.

When implanted within the tongue, the implants of the disclosure provideforces and displacements to the tongue to allow the patient's airway toremain open during normal breathing when the patient is asleep and fullyrelaxed. The maximum displacement of the tongue that does not result inundesired side effects, as mentioned above, is referred to as themaximum threshold displacement for therapeutic benefit. This maximumthreshold displacement for one or more implants within or adjacent tothe tongue is between about 0.5 mm and about 20 mm in some embodiments,between about 1.0 mm and about 15 mm in other embodiments, and betweenabout 1.0 mm and about 10.0 mm in still other embodiments.

When implanted within the soft palate, the implants of the disclosurecan provide forces and displacements to the soft palate to allow thepatient's airway to remain open during normal breathing when the patientis asleep and fully relaxed. The maximum displacement of the soft palatethat does not result in undesired side effects, as mentioned above, isreferred to as the maximum threshold displacement for therapeuticbenefit. This maximum threshold displacement for one or more implantswithin or adjacent to the soft palate is from 0.5 mm to 5.0 mm in someembodiments.

When implanted in the tongue, the implants of the disclosure may providean effective therapeutic window of operation bounded by a minimumthreshold force required to prevent the tongue from obstructing theairway during normal breathing when the patient is asleep and relaxed,and by a maximum displacement threshold above which the implant(s)adversely affects normal airway and tongue function including speech,swallowing, breathing, etc. This effective therapeutic window isidentified based on the forces and displacements described above.

When implanted in the soft palate, the implants of the disclosure mayprovide an effective therapeutic window of operation bounded by aminimum threshold of force required to prevent the soft palate fromobstructing the airway when the patient is asleep and relaxed, and by amaximum displacement threshold above which the implant(s) adverselyaffects normal airway or mouth function including speech, swallowing,breathing, etc. This effective therapeutic window is identified based onthe forces and displacements described above.

Implant Force/Motion Directions within the Tongue. When the one or moreimplants of the disclosure are employed within the patient's tongue toprevent airway occlusion when said patient is asleep and fully relaxed,said implant(s) provide sufficient force to open the airway duringnormal breathing. One or more implants may be employed to apply thedesired forces and deflections to the patient's tongue. Said implantsmay be employed in one or more locations within or adjacent to thetongue, they may be anchored in one or more locations within or adjacentto the tongue, and they may apply forces and/or deflections in one ormore directions and between two or more locations within or adjacent tothe tongue.

Said implants may be employed in such a manner as to relieveobstructions in the airway caused by the tongue resulting in OSA.Generally, this includes displacing the posterior region of the tongueand/or providing forces on the posterior region of the tongue that pullsaid posterior region in the anterior direction, away from the posteriorpharynx wall, resulting in preventing the opening of the airway fromclosing such that normal breathing can be maintained. Said forces and/ordisplacements may act to affect the entire posterior region of thetongue, a very specific location in the posterior region of the tongue,a linear area of affect in the posterior region of the tongue (i.e., alinear area that runs cranially and caudally so as to create a channelthrough which the airway remains patent), or any combination of theabove.

In one exemplary embodiment, a single implant is employed to apply aforce to the posterior region of the tongue in an approximatelyhorizontal anterior direction as viewed in a patient standing straightup with their head facing forward (FIG. 24). In another exemplaryembodiment, a single implant is employed to apply a force to theposterior region of the tongue at an inclined angle to the horizontal,and in the anterior direction as viewed in a patient standing straightup with their head facing forward (FIG. 25).

In another embodiment of the invention, three implants are employedwithin the tongue to apply forces to the posterior region of the tonguein such a manner as to advantageously create a longitudinal open regionbetween said tongue and the posterior pharyngeal wall, running in thedirection of air motion during normal breathing. The three implants inthis embodiment are acting in different directions to create the desirednet distribution of forces and displacements on the tongue (FIG. 26). Inanother embodiment of the invention, four implants are employed withinthe tongue to apply forces distributed throughout the tongue, with theimplants acting in different directions to create the desired netdistribution of forces and displacements on the tongue (FIG. 27).

When more than one implant is used, the set of implants may all lie inany orientation with regard to each other and the surrounding anatomicalstructures, including in a linear arrangement, a parallel arrangement, aplanar array (including but not limited to a triangulated structure), athree-dimensional array, or any combination of these arrangements. Theimplants may be joined together in any multi-linear, non-linear, ormultiply-linearly segmented manner. One example is described above inFIGS. 28A-28C, wherein two linear elastic or spring elements 720A and720B are connected to provide a common anchor point 725 a in tissue atone end of each of the two said linear elements, respectively. The otherends of the first and second linear elements provide additional anchorpoints 725 b and 725 c in the tissue. In this manner, anchor points 725b and 725 c are pulled in the direction of the common anchor 725 a so asto provide a bi-linear implant structure. By extension, and in thismanner, complex multi-linear structures or networks of linear elementsmay be constructed to achieve the desired clinical effects. Similarly,two or more implants comprising multi-linear components may be employedin conjunction to achieve the desired clinical effects. Alternately, theelastic or spring elements may be fabricated in such a fashion as toproduce a joined, jointed, or linked structure during the manufacturingprocess.

Implant Force/Motion Directions within the Soft Palate. When the one ormore implants of the disclosure are employed within the patient's softpalate to prevent airway occlusion when said patient is asleep and fullyrelaxed, said implant(s) provide sufficient force to open the airwayduring normal breathing. One or more implants may be employed to applythe desired forces and deflections to the patient's soft palate. Saidimplants may be employed in one or more locations within or adjacent tothe soft palate, they may be anchored in one or more locations within oradjacent to the soft palate, and they may apply forces and/ordeflections in one or more directions and between two or more locationswithin or adjacent to the soft palate.

Said implants may be employed in such a manner as to relieve or preventobstructions in the airway caused by the soft palate resulting in OSA.Generally, this includes displacing the posterior region of the softpalate and/or providing forces on the posterior region of the softpalate that pull said posterior region in the anterior direction awayfrom the posterior wall of the pharynx resulting in the opening of theairway during normal breathing. More specifically, said implants withinsaid soft palate tend to cause a curvature of the soft palate in thedownward and anterior direction to affect said opening of said airway.Said forces and/or displacements may act to affect the entire posteriorregion of the soft palate, a very specific location in the posteriorregion of the soft palate, a linear area of affect in the posteriorregion of the soft palate, or any combination of the above.

In one exemplary embodiment, a single implant is employed to apply aforce to the posterior region of the soft palate resulting in acurvature of said soft palate that displaces said soft palate away fromthe pharynx wall. In another embodiment of the invention, two implantsare employed within the soft palate at differing angles and in differentlocations to apply forces and displacements to the soft palate resultingin a curvature of said soft palate that displaces said soft palate awayfrom the pharynx wall.

The above-described OSA implants in FIGS. 24-37 generally describeimplant bodies and methods that are adapted to apply linearly-directedforces to airway interface tissue. Other embodiments described nextrelate to implants configured to displace tissue or apply forces innon-linear vectors, which can be used alone or in combination with thelinear force-directing implant described previously. In one embodiment,FIGS. 38A-38B depict an elastic OSA implant 900 with anchor ends 902 a,902 b that is curved in a repose state and can be implanted in either acurved or linear path, for example, in a vertical orientation in thepatient's tongue (FIG. 38A). In FIG. 38B, it can be seen that if tonguebase 904 is displaced posteriorly, the implant will be moved toward astraightened configuration wherein the elastic implant will apply forcesanteriorly and upward to prevent airway interference. The implant ofFIGS. 38A-38B can have any suitable ends for anchoring in tissue, forexample, end portions with one or more openings resulting in tissueplugs anchors as described above.

FIG. 39 depicts a curved implant 910 similar to that of FIGS. 38A-38Bimplanted in a horizontal plane in the patient's tongue. The implant 910thus partly encircles tissue and applies forces in multiple vectors whenstretched to move the tongue forward away from the airway. The implantof FIG. 39 can be implanted using a curved introducer as describedpreviously.

FIGS. 40A-40B depicts another implant 920 that has a serpentine orS-shape in a repose condition in a patient's tongue. As can beunderstood from FIG. 40B, if the tongue base 904 is displacedposteriorly, the implant will be stretched and the elastic implant willapply forces anteriorly and toward the serpentine condition to compresstongue tissue to prevent airway interference. FIG. 41 depicts anotherimplant 930 that has a helical shape in its repose condition in apatient's tongue. This implant 930 would function as the serpentineimplant of FIGS. 40A-40B to apply compressive and anteriorly directedforces to the patient's tongue.

FIG. 42 depicts another type of OSA implant 940 that comprises a loop ortissue-encircling implant at least partly of an elastic material thatencircles tongue tissue or other airway-interface. Such an encirclingimplant 940 can be implanted using introducer systems described furtherbelow, wherein first and second end portions 942 a and 942 b of theimplant are coupled by connection means which can be clips, snap-fitfeatures, pins, ratchets, sutures, stakes, clamps, welds, fusiblematerials, adhesives and the like indicated at 945. The portion betweenthe ends may have a long curvilinear axis, wherein the medial portion isconfigured to tensile forces along the axis. Such an encircling implantcan apply inwardly-directed, elastic and compressive forces on encircledtissue which may cause tissue to remodel to provide a reduced tissuevolume. At the same time, the elastic encircling implant will applyforces in a plurality of vectors to return the implant and engagedtissue that is outside the encircling loop toward the repose shape ofthe implant and engaged tissue within its path in the targeted site. Theimplant of FIG. 42 can be configured with the bioerodible elements asdescribed previously to allow the forces to be applied to the tissueslowly over a selected time interval. Still referring to FIG. 42, theencircling implant has anterior portion 946 that extends in first andsecond legs to the cross-over posterior portion 948, wherein the first(anterior) portion 946 has a first elasticity and the second (posterior)portion has a second elasticity. In one embodiment, the anterior implantportion 946 has greater elasticity than the posterior portion 948, andthe posterior portion is adapted to distribute applied forces over aregion of the tongue. In another aspect, the posterior region may havemore than one elasticity.

FIG. 43 depicts an encircling OSA implant 950 similar to that of FIG. 42except that the tissue-encircling implant is placed in a horizontalorientation in the patient's tongue. It should be appreciated that aplurality of encircling implants such as those of FIGS. 42 and 43 can beimplanted in a patient.

FIG. 44A depicts an introducer system 960 that is adapted forimplantation of an encircling-type implant such as the OSA implant ofFIG. 42. The introducer system 960 is shown schematically and includesfirst and second trocar elements, 962A and 962B, a guide block or member964 which is configured to guide the trocars in a predetermineddirection and relative angle when the trocars are extended from theguide block 964 into tissue. Further, the system 960 includes push-pullrods or controlling rods 965A and 965B that are slidably carried inrespective bores of the trocar elements, 962A and 962B. In FIGS. 44A and44B, it can be seen that a releasable, flexible tunneling element 966that is pre-formed in curve with a sharp tip 968 is releasably coupledto control rod 965A. The distal end of tunneling element 966 isconfigured with an opening 970 or other grip feature that allows for itscoupling to second control rod 965B. The tunneling element 966 has apreformed curvature and can be made of a shape memory alloy (e.g., NiTi)such that when the tunneling element is advanced from the distal port972A of trocar element 962A, the element tunnels in a curved path to thedistal port 972B of the other trocar element 962B.

FIG. 44B depicts a cut-away schematic view of the working end of thesystem of FIG. 44A in a method of use, wherein the distal portions ofthe trocar elements 962A and 962B are shown as if advanced from theguide block 965 into a targeted tissue site. FIG. 44B shows thetunneling element moved from retracted position (not shown) in apassageway in trocar element 962A to a first extended position outwardof port 972A. It can be seen that an encircling implant 940 of the typeshown in FIG. 42 is releaseably coupled to tunneling element 966. Insome embodiments, coupling is achieved by means of a hook on thetunneling element that holds the implant while the tunneling element andimplant advance through tissue. The hook is released upon retraction ofthe tunneling element. In another embodiment, coupling is achieved bymeans of a clasp or other means well understood by those of skill in theart. FIG. 44C depicts the next step of the method wherein the curvedtunneling element 966 is extended further by advancing rod 965A untilthe distal end of tunneling element 966 enters port 972B of the opposingtrocar element 962B. Thereafter, control rod 965B is moved proximallywherein an engaging hook or other engagement element 975 engages theopening 970 in the tunneling element 966.

FIG. 44D depicts a subsequent step wherein control rod 965B is movedfurther in the proximal direction and the OSA implant 940 is pulledthrough the path in tissue created by the tunneling element 966 and theninto port 972B of the trocar element 962B. FIG. 44E depicts another stepwherein the implant 940 is disposed with ends 942 a and 942 b fullybridging between the opposing trocar elements 962A and 962B, such thatthe physician can prepare to withdraw both trocar elements from thetissue site to thereby release the implant and leave the implant inplace in the encircling tissue.

Now turning to FIGS. 44F and 44G, the steps relating to FIG. 44E areshown schematically in an optional sub-mandibular access to thepatient's tongue. FIG. 44F depicts the implant 940 fully bridged betweenthe trocars 962A and 962B as in FIG. 44E. FIG. 44G shows the trocarelements 962A and 962B withdrawn leaving then implant 940 in place. FIG.44H then depicts the final step of the method wherein the first andsecond ends 942 a and 942 b of the implant 940 are attached to one otherby any attachment means 945 as described above of by tissue fibrosis asdescribed above to thereby provide an encircling implant. In oneembodiment, implant ends are attached to each another by means of tissuefibrosis. Tissue fibrosis may be induced by having the ends of theimplant in sufficiently close proximity to one another such that thefibrotic responses to the implants substantially come in contact withone another. Tissue fibrosis may be induced as a consequence oftunneling (e.g. using trocar or stylet or other means) through thetissue to create a channel through some or all of the gap between theimplant ends. The healing response to the channel creates the fibroticresponse.

FIG. 45 depicts various shapes and configurations of loop or encirclingimplants 980 a-980 h.

FIG. 46 depicts a loop or encircling implant 980 a with its ends fixedlyconnected around the geniohyoid muscle 982 to serve as an anchor.

FIG. 47 depicts a U- or V-shaped implant 985 with two anchor ends 986 aand 986 b as described previously in an anterior position adjacent tothe mandible 987. This implant can be placed by the same method as inFIGS. 44A-44H above, except that the ends 986 are not connected in afinal step of the method.

FIGS. 48-49 depict a V-shaped implant 900 with two anchoring portions902 a and 902 b at the distal ends of legs of the V-shape. FIG. 48 showsimplant 900 in a horizontal orientation, and FIG. 49 shows the implant900 in a vertical orientation. FIGS. 50A-50C schematically illustrate anapparatus and method for implanting such V-shaped implants through asingle entry point. In FIG. 50A, the disclosure provides a trocar 905with a sharp-tipped trocar sleeve 910 that can be inserted into tissue.A passageway 912 in the trocar sleeve 910 carries first and secondcurved tunnelers 915A and 915B that can be extended into tissue to formpockets to accept the legs of a V-shaped implant, such as the V-shapedimplant 900 that is shown in FIG. 49. A tunneler may have a resilientcurved end. A tunneler may be comprised of a shape memory alloy. It canbe understood that tunnelers 915A and 915B have a U-shaped transversesectional shape wherein the longitudinal slot allows for release anddeployment of the implant. FIG. 50B depicts the tunnelers 915A and 915Bbeing withdrawn proximally wherein stylets 920A and 920B maintain theimplant 900 in the targeted location by grasping implants ends 902 a and902 b. FIG. 50C depicts the V-shaped implant 900 in its final deployedlocation wherein the implant ends 902 a, 902 b will be anchored in thetissue with tissue plugs as described previously.

FIG. 51 illustrates a V-shaped implant 900 as in FIGS. 50A-50C anchoredaround the geniohyoid muscle 982.

FIG. 52 illustrates an alternative OSA implant 920 that comprises acombination of previously described features wherein the implantincludes an encircling portion 925 with attachment means 928 that iscoupled to a linear implant portion 930 that extends to an anchoring end935 that is configured with an opening 936 therein for tissue growththerethrough. The encircling portion 925 encircles the geniohyoid muscle982.

In another aspect of the invention, referring to FIG. 53, an implant1000 and method are provided for limiting the pressure applied by theimplant to the patient's tongue. In FIG. 53, it can be seen that theelongated implant body is configured for treating an airway disorder byimplantation in a patient's tongue, wherein a first end portion 1002A ofthe implant is within an anterior region of the tongue and a second endportion 1002B is in close proximity to a posterior surface 1004 of thetongue. As described in previous embodiments, the medial portion 1010 ofthe implant body comprises an elastomeric or spring material that isconfigured to apply tensioning forces to tissue. In this embodiment, themedial portion 1010 can comprise a silicone elastomer or metal springembedded in a biocompatible elastomer that is designed to providepressures of less than 20 kPa during normal physiological functioning ofthe patient's tongue. For clarity, it can be understood that the medialimplant portion 1010 will be stretched during tongue function, and themaximum pressure of 20 kPa would thus occur when the implant isstretched to the maximum extent during normal function of the tongue,for example during swallowing. In other embodiments, the medial portion1010 of the implant 1000 of FIG. 53 can be configured to apply apressure of less than 15 kPa, less than 10 kPa or less than 5 kPa.

In general, the invention provides a method of treating an airwaydisorder comprising placing an implant in a patient's tongue wherein theimplant has first and second end portions that attach to tissue and atensioned medial portion between the first and second ends, wherein themedial portion is configured to apply a pressure of less than 20 kPa,less than 15 kPa, less than 10 kPa or less than 5 kPa.

In another aspect of the invention, it is desirable to distribute forcesapplied by the implant, as in FIG. 53, over a broad area of the tongueto prevent point loads on tissue which could cause tissue dissection,tissue damage or unwanted tissue remodeling. For this reason, referringto FIG. 53 it can be seen that the second end 1002B of the implant bodyhas a planar shape with a cross-section that is substantially largerthan the cross-section of the medial extension portion 1010. The planarend portion 1002B can comprise hooks, prongs, loops, mesh, porousstructures or any combinations thereof and in FIG. 53 it can be seenthat a mesh 1012 is surrounded by a loop element. In one embodiment, thecross-sectional area of the second end is at least 500% of thecross-sectional area of the medial extension portion 1010. In otherembodiments, the cross-sectional area of the second end portion is atleast 750% of the cross-sectional area of the extension portion, or atleast 1,000% of the cross-sectional area of the extension portion.

In another aspect of the invention, an implant body 1050 is provided asdepicted in FIG. 54 that is configured with a different mechanism toprevent excessive pressures being applied to the tissue, andparticularly to the anchoring end portions of the implant body. In theembodiment of FIG. 54, a release mechanism is provided which can includea projecting element 1058 that is gripped by a surrounding gripstructure such as polymer flex arms or elements 1060 connected to thesecond portion of the extension member 1055. It can be understood thatunder a certain force, the flex arms 1060 can flex to thus release theprojecting element 1058. In general, a method for treating an airwaydisorder comprises providing an elongated implant for implanting in apatient's tongue, wherein the implant comprises an extension memberhaving first and second end portions and an intermediate release elementthat releases the first end portion from the second end portion upon apreselected pressure on the tongue tissue above the implant, whichtranslates to a force applied to flex arms 1060. The pressure can beless than 20 kPa, less than 15 kPa, less than 10 kPa or less than 5 kPa.In this embodiment, the implant body 1050 will post-failure have theimplant with disconnected end, and a minor surgery can be used torevise, remove, re-couple or otherwise adjust the implant.

In another embodiment (not shown) the extension portion of the implantcan have a ratchet mechanism that allows the implant to slip betweenvarious ratchet elements to thereby adjust the overall length of theimplant after when forces exceed a predetermined value as describedabove.

In another embodiment (not shown) the extension portion of the implantcan have a ratchet mechanism that allows for user manipulation to adjustthe overall length of the implant. For example, if the implantexperiences force requirements greater than a pre-selected level, thenthe user can manipulate the implant with his fingers to return the firstand second end to ratchet toward a shorter overall length of the implantbody to allow the implant to apply more force.

In another embodiment, the implant body can be configured with atransponder or RFID type of mechanism which upon an electromagneticquery signal from a remote source, the coil and circuitry in the implantwill respond with an electromagnetic answer signal indicating anoperational parameter of the implant, for example the implant's length.In another example, the query signals could be periodic or continuousduring a patient's sleep to provide information on pressure or forceparameters. In one aspect, the invention would be useful for implantsthat are length-adjustable by the patient, so that the patient canadjust the length before and/or after a sleep interval.

In general, a method for treating an airway disorder comprisesimplanting an implant body into airway-interface tissue wherein theimplant body is sized and shaped to conform in a manner compatible withnormal physiological function of the site and to apply selected forcesto the tissue, and wherein the implant is configured to receive anelectromagnetic query and to respond with an electromagnetic signalindicating an operational parameter of the implant body during saidnormal physiological function of the site.

The embodiments of implants shown in the figures above can be sized andshaped to conform to a treatment site in a patient's tongue, palate orother site in airway-interface tissue and to reside in an orientationand in a manner compatible with normal physiological function of thesite. The overall dimensions may vary according to the full extent thathuman subjects vary in their anatomical dimensions, and thus thedimensions provided here are only an approximation for the purpose ofillustration, and are not meant to be limiting. Any embodiment in itselongated state may typically be in the range of about 2 cm to about 10cm in length in a releasably extended state, and the implant in acontracted state may be in the range of about 1 cm to about 6 cm inlength. Testing shows there is an advantage to using these lengths.

Unless defined otherwise, all technical terms used herein have the samemeanings as commonly understood by one of ordinary skill in the art towhich this invention belongs. Specific methods, devices, and materialsare described in this application, but any methods and materials similaror equivalent to those described herein can be used in the practice ofthe present invention. While embodiments of the inventive device andmethod have been described in some detail and by way of exemplaryillustrations, such illustration is for purposes of clarity ofunderstanding only, and is not intended to be limiting.

Various terms have been used in the description to convey anunderstanding of the invention; it will be understood that the meaningof these various terms extends to common linguistic or grammaticalvariations or forms thereof. It will also be understood that whenterminology referring to devices or equipment has used trade names,brand names, or common names, that these names are provided ascontemporary examples, and the invention is not limited by such literalscope. Terminology that is introduced at a later date that may bereasonably understood as a derivative of a contemporary term ordesignating of a subset of objects embraced by a contemporary term willbe understood as having been described by the now contemporaryterminology.

While some theoretical considerations have been advanced in furtheranceof providing an understanding of the invention the claims to theinvention are not bound by such theory. Described herein are ways thatembodiments of the invention may engage the anatomy and physiology ofthe airway, generally by opening the airway during sleep; thetheoretical consideration being that by such opening of the airway, theimplanted device embodiments alleviate the occurrence of apneic events.Moreover, any one or more features of any embodiment of the inventioncan be combined with any one or more other features of any otherembodiment of the invention, without departing from the scope of theinvention. Further, it should be understood that while these inventivemethods and devices have been described as providing therapeutic benefitto the airway by way of intervention in tissue lining the airway, suchdevices and embodiments may have therapeutic application in other siteswithin the body, particularly luminal sites. Still further, it should beunderstood that the invention is not limited to the embodiments thathave been set forth for purposes of exemplification, but is to bedefined only by a fair reading of claims that are appended to the patentapplication, including the full range of equivalency to which eachelement thereof is entitled.

1. A method of treating an airway disorder comprising placing an implantin a patient's tongue wherein the implant has first and second endportions that attach to tissue and a tensioned medial portion betweenthe first and second ends, wherein the medial portion is configured toapply a pressure of less than 20 kPa.
 2. The method of claim 1 whereinthe medial portion is configured to apply a pressure of less than 15kPa.
 3. The method of claim 1 wherein the medial portion is configuredto apply a pressure of less than 10 kPa.
 4. The method of claim 1wherein the medial portion is configured to apply a pressure of lessthan 5 kPa.
 5. A method of treating an airway disorder comprisingplacing an elongated implant in a patient's tongue wherein the implanthas first and second ends and an extension portion therebetween, whereinthe second end is implanted in proximity to a posterior surface of thetongue, and wherein the cross-sectional area of the second end is atleast 500% of the cross-sectional area of the extension portion.
 6. Themethod of claim 5 wherein the cross-sectional area of the second end isat least 750% of the cross-sectional area of the extension portion. 7.The method of claim 5 wherein the cross-sectional area of the second endis at least 1,000% of the cross-sectional area of the extension portion.8. The method of claim 5 wherein the second end comprises at least oneof mesh, hooks, prongs, loops, or porous surfaces.
 9. The method ofclaim 5 wherein the first end comprises at least one of mesh, hooks,prongs, loops, or porous surfaces.
 10. An implant for treating an airwaydisorder comprising an elongated implant for implanting in a patient'stongue, the implant comprising an extension member having first andsecond end portions and an intermediate release element that releasesthe first end portion from the second end portion upon a preselectedpressure.
 11. The implant of claim 10 wherein preselected pressure isbetween 1 kPa and 20 kPa.
 12. The implant of claim 10 whereinpreselected pressure is between 5 kPa and 20 kPa.
 13. The implant ofclaim 10 wherein preselected pressure is between 1 kPa and 20 kPa. 14.The implant of claim 10 wherein releasing the release element decouplesthe first and second end portions.
 15. The implant of claim 10 whereinreleasing the release element alters the length of the extension member.16. An implant for treating an airway disorder comprising an elongatedimplant for implanting in a patient's tongue, the implant having firstand second end portions and a medial portion, the medial portioncomprising an elastic material configured to apply a tensioning force ofless than 20 kPa during normal physiological function of the patient'stongue.
 17. The implant of claim 16 wherein the elastic material isconfigured to apply a tensioning force of less than 10 kPa.
 18. Theimplant of claim 16 wherein the elastic material is configured to applya tensioning force of less than 5 kPa.